The present invention relates to the method for extracting the oil content from rocks and stones containing oil such as, for example, oil shale.
There are huge amounts of oil shale reserves in the United States and Canada, and it is well known that such oil shale contains approximately 17% of petroleum.
Conventionally, the oil from oil shale has been extracted by dry distillation by means of steam or at high temperatures. However, these methods are disadvantageous in that it is necessary to heat the oil shale to 400.degree. C. or higher and energy resources, such as fuel for heating the oil are expensive and not feasible on an economical basis.